Additional setings are available when "Record Audio" is selected.
There are two combo boxes. The "Audio Device" combo box shows the audio recording hardware in your system. Normally it should only show the sound card. If you have 1394 capture card installed and a DV camcorder connected, you can see the DV camcorder here too.
Occasionally, your system would put your modem in this list too. You want your audio card selected in the "Audio Device" combo.
If you have built-in audio chipset on your motherboard, and added a PCI sound card later, it will show both in the "Audio Device" combo if you did not disable the motherboard audio. Please disable the built-in audio chipset according to your motherboard manual. Having both may cause conflicts.
The "Port" combo box shows a list of connection options on the sound card. This list is provided by the OS and audio driver. Most of the time, you should only care about the following connections. Note, different audio driver may give different names.
Microphone
Mic
The audio will be captured from the microphone port.
Line-in
Line In
The audio will be captured from the Line-in port
Stereo Mix
Mono Mix
WAV
WAV Out Mix
The audio will be capture from the sound card's speakers.
You can let the sound card adjust the volume automatically, or set the level manually. When "Manual" is selected, a slider is shown to the right. Use this slider to set the volume level.